Method and apparatus for reporting radio bearer loss information

ABSTRACT

A method for reporting radio bearer loss information is provided in an embodiment of this invention. The method comprises: receiving a User Equipment UE Context Release Request message or a Release Access Bearer Request message or an Iu interface release request message all carrying a release cause value; and if the release cause value indicates an abnormal release, reporting radio bearer loss information to a gateway while preserving non-GBR bearers. With the method and apparatus of embodiments of this invention, not only bearer reporting can be realized, but also problems caused by the release of Non-Guaranteed Bandwidth non-GBR bearers can be prevented.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Patent ApplicationNo. PCT/CN2010/076194, filed on Aug. 20, 2010, which is herebyincorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to the communication field, and morespecifically, to a method and apparatus for reporting radio bearer lossinformation.

BACKGROUND OF THE INVENTION

Bearers of next generation communication networks have been moving to IP(Internet Protocol, internet protocol) bearers. From the perspective ofthe development of communication networks, a progress, from traditionalcircuit switch networks to IP packet switching networks withcontrol-bearer separation, and then to all IP multimedia networks, hasbeen experienced. End-to-end QoS (Quality of Service, quality ofservice) issues have to be considered during the evolution to all IPnetworks to provide customer with satisfied services (particularly,real-time services). Because IP networks may provide more kinds ofservices (such as, multimedia call, file download, webpage browse, etc),it is necessary to enable networks to detect different service streams,perform statistics on charging information, such as traffic amount,duration etc, and report to charging centers. In order to solve the QoSand stream-based charging issues, a PCC (Policy and Charging Control,policy and charging control) framework has been defined by 3GPP (ThirdGeneration Partnership Project, third generation partnership project).The networks are able to detect different service streams and QoScontrol, charging statistic and other requirements can be realized forthose service streams through the framework.

In the PCC framework, a UE (User Equipment, user equipment) canestablish an IP-CAN (IP-Connectivity Access network, IP-connectivityaccess network) session after assigned with an IP address which isaddressable in the PDN (Public Data Network, public data network). Inorder to satisfy different QoS requirements, IP-CAN bearers (Bearer)with different QoS requirements can be established in a same IP-CANsession. For IP-CAN bearers, they can be categorized into GBR(Guaranteed Bandwidth, GBR) bearers and non-GBR bearers, wherein thedefault is non-GBR. In general, GBR bearers are used forbandwidth-sensitive real-time services, such as, VoIP (Voice overInternet Protocol, voice over internet protocol) media stream, videostream, etc; while non-GBR bearers are used for bandwidth-insensitivenon-real time services and some real-time services having less bandwidthrequirements, such as FTP (File Transfer Protocol, file transferprotocol) download, HTTP (Hyper Text Transfer Protocol, hypertexttransfer protocol) browse, email (electronic mail, electronic mail),VoIP signaling stream etc.

Presently, operators can realize excellent control over QoS and chargingetc for bearer-layer data streams through the PCC framework, to shieldupward particular transport network details from the service layer andsense downward transport network resource usage. On one side, PCRF(Policy and Charging Rule Function, policy and charging rule function)may develop corresponding strategies according to session negotiationinformation indicated by the service layer to control bearer-layernetwork resource use; on the other side, when the use of underlyingbearers has changed, for example, radio bearer loss due to a userentering a uncovered area, a gateway fault, etc, the service layer canbe notified through a reporting mechanism, enabling the service layer tochange accordingly, provide corresponding strategies.

However, in the prior art, when an eNB (eNodeB, Evolved Node B) needs torelease the signaling connection with a UE and its all radio bearers, aPGW (PDN Gateway, Packet Data Network Gateway, packet data networkgateway) is notified through a bearer release mechanism, thereby thePCRF and AF (Application Function, application function) are notified.For GBR (Guaranteed bandwidth, guaranteed bandwidth) bearers, since theyare substantially adopted for real-time service transport, abnormallyreleased radio bearers, even for a short time, may cause serviceinterrupts, the release of GBR bearers is reasonable. However, fornon-GBR bearers, adopting a mechanism releasing non-GBR bearers mayaffect other services bound to those non-GBR bearers, and lead to an IPaddress release defect caused by the release of default bearers.

SUMMARY OF THE INVENTION

A method and apparatus for reporting radio bearer loss information areprovided in embodiments of this invention, for solving the problems ofaffecting services bound to other non-GBR bearers and IP addressreleasing due to the release of a default bearer, caused in a radiobearer loss information reporting mechanism realized through releasingnon-GBR bearers after radio bearers are abnormally released.

The above objects of embodiments of this invention are realized throughthe following technical solutions:

a radio bearer loss information reporting method, said method comprises:receiving a User Equipment UE Context Release Request message or aRelease Access Bearer Request message or an Iu Interface Release Requestmessage all carrying a release cause value; if the release cause valueindicates an abnormal release, reporting radio bearer loss informationto a gateway while preserving Non-Guaranteed Bandwidth non-GBR bearers.

A Mobility Management Entity MME, said MME comprises: a receiving unitfor receiving a UE Context Release Request message carrying a releasecause value sent by an Evolved Node B eNB; a reporting unit for when therelease cause value indicates an abnormal release, reporting a radiobearer loss information to a gateway; a processing unit for, when therelease cause value indicates an abnormal release, preserving non-GBRbearers.

A Serving Gateway SGW, said SGW comprises: a receiving unit forreceiving a Release Access Bearer Request message carrying a releasecause value sent by a MME; a reporting unit for when the release causevalue indicates an abnormal release, reporting radio bearer lossinformation to a PGW; a processing unit for when the release cause valueindicates an abnormal release, preserving non-GBR bearers.

A Serving GPRS support Node SGSN, said SGSN comprises: a receiving unitfor receiving an Iu Interface Release Request message carrying a releasecause value sent by a Radio Network Controller RNC; a reporting unit forwhen the release cause value indicates an abnormal release, reportingradio bearer loss information to a gateway; a processing unit for whenthe release cause value indicates an abnormal release, preservingnon-GBR bearers.

With the method and apparatus of the embodiments of this invention, notonly the report of radio bearer loss information can be realized, butalso problems caused by the release of non-GBR bearers can be avoided.

BRIEF DESCRIPTION OF THE DRAWINGS

Accompanying drawings described herein are given to provide a furtherunderstanding of this invention, which are part of this application, butare not limits of this invention, in which:

FIG. 1 is a flowchart of a method of reporting radio bearer lossinformation according to an embodiment of this invention;

FIG. 2 is a flowchart of reporting radio bearer loss information by aMME according to the method shown in FIG. 1;

FIG. 3 is a flowchart of reporting radio bearer loss information by aSGW according to the method shown in FIG. 1;

FIG. 4 is a flowchart of reporting radio bearer loss information by aSGSN according to the method shown in FIG. 1;

FIG. 5 is a flowchart of a method of reporting radio bearer lossinformation according to another embodiment of this invention;

FIG. 6 is a flowchart of a first embodiment in which radio bearer lossinformation is reported by a MME according to the method shown in FIG.5;

FIG. 7 is a flowchart of a second embodiment in which radio bearer lossinformation is reported by a MME according to the method shown in FIG.5;

FIG. 8 is a component block diagram of a MME provided in an embodimentof this invention;

FIG. 9 is a component block diagram of a SGW provided in an embodimentof this invention;

FIG. 10 is a component block diagram of a SGSN provided in an embodimentof this invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to make the objects, technical solutions and advantages ofembodiments of this invention clearer, in connection with embodimentsand accompanying drawings, a more detailed description will be given toembodiments of this invention. Herein, illustrative embodiments of thisinvention and their description are merely for the explaining of thisinvention, but not limits of this invention.

FIG. 1 is a flowchart of a method of reporting radio bearer lossinformation provided in an embodiment of this invention. The method isapplied on a network-side device, such as a MME (Mobile ManagementEntity, mobile management entity) or a SGW/SGSN (Service GPRS SupportingNode, service GPRS (General Packet Radio Service) supporting node), inwhich the MME/SGW/SGSN is responsible for the radio bearer lossinformation reporting. Referring to FIG. 1, the method comprises thefollowing steps:

Step 101: receiving a UE Context Release Request message or ReleaseAccess Bearer Request message or Iu interface release request messageall carrying a release cause value.

In one embodiment, when a device on the radio access network side (suchas eNB) detects that it is necessary to release a radio signalingconnection to a UE and all radio bearers, a UE Context Release Requestmessage carrying a release cause value is transmitted to a network-sidedevice (such as a MME), to notify the MME of the interruption of theradio connection to the UE. At that point, the MME will report radiobearer loss information after receiving the UE Context Release Requestmessage.

In another embodiment, after receiving the UE Context Release Requestmessage, instead of reporting radio bearer loss information, the MMEwill forward a release cause value to a SGW through a Release AccessBearer Request message, and the SGW then performs the reporting of radiobearer loss information.

In another embodiment, when a device on the radio access network side(such as RNC) detects that it is necessary to release a radio signalingconnection to a UE and all radio bearers, an Iu interface releaserequest message carrying a release cause value is transmitted to anetwork-side device (such as a SGSN), to notify the SGSN of theinterruption of the radio connection to the UE. At that point, afterreceiving the Iu interface release request message, the SGSN will reportradio bearer loss information.

Wherein, the release cause value is used to indicate the reason for therelease, such as radio connection with UE lost, management maintenancecause, user inactivity, or repeated unsuccessful integrity checks withthe UE, etc. When the release cause value is any one of radio connectionwith UE lost, management maintenance cause, or repeated unsuccessfulintegrity checks with the UE, etc, an abnormal release can be confirmed.

Step 102: if the release cause value indicates an abnormal release,radio bearer loss information is reported to a gateway while all non-GBRbearers are preserved.

Wherein, after the MME/SGW/SGSN has received a corresponding messagecarrying a release cause value, it is determined whether to report aradio bearer loss information according to the release cause value, ifthe release cause value indicates an abnormal release, that is, therelease cause value is any one of the radio connection with US lost, themanagement maintenance cause, or the repeated unsuccessful integritychecks with the UE, a UE radio bearer loss information is reported tothe gateway, while all non-GBR bearers are still preserved on theMME/SGW/SGSN.

For non-GBR services, not all of which may make services interruptedwhen radio bearers are released abnormally, such as HTTP, FTP, email,P2P (peer-to-peer, peer-to-peer), all of which can allow short transportinterruption, especially for the case of restoring radio connection soonafter entering an uncovered area occasionally by a UE. According to thecurrent bearer binding mechanism, one bearer can be bound to severalservices with the same QoS requirements, and if some of the servicestake care of bearer events but others not, adopting the bearer releasemechanism may cause those services taking no care of bearer eventsunable to transmit over the bearer (because the bearer has beenreleased), even if these services can endure occasional interrupt.Further, for non-GBR services, concerning bearer events may notnecessarily cause service interruption in abnormal radio bearer release.

Because the default bearer is non-GBR bearer, if such servicenecessarily taking care of bearer events is transmitted over a defaultbearer, adopting such a mechanism may release the default bearer, whichin turn may cause the release of the whole IP-CAN session, including allbearers, and release its IP address, leading to the release of non-GBRbearers which are pre-labeled as pre-preserved. Further, after therelease of the IP address, when the radio connection is restored againby the UE, an attaching process has to be performed and an IP addresshas to be assigned again, which may cause a large amount of signalinginteractions, resulting to unnecessary signaling interactions.

With the method of reporting a radio bearer loss information provided inthe embodiment of this invention, the problem of non-GBR bearerinterrupting, no matter whether the service can endure bearer loss onthe radio side, which is caused by adopting a bearer release mechanismfor non-GBR bearers to notify a gateway after receiving a radio sidebearer loss information by a network-side device MME/SGSN, and with adeployed PCC, notify the PCRF by the gateway; and the problem of IPaddress releasing due to the release of the default bearer and thus therequirement of reattachment, can be solved.

In order to make the method of the embodiment of FIG. 1 clearer, themethod of this embodiment will be described in detail in connection withthe flow shown in FIGS. 2 to 4.

FIG. 2 is a flowchart of a method according to the embodiment, in whicha MME is responsible for the reporting of radio bearer loss information.The embodiment directs to the EPS (Evolved Packet System) defined by the3GPP standard organization, with eUTRAN (evolved universal terrestrialradio access network) as a radio access technique. Referring to FIG. 2,the flow comprises the following steps:

Step 201: if an eNB detects that it is necessary to release a signalingconnection to a UE (user equipment) and all radio bearers, it sends S1 aUE Context Release Request (context release request) message to a MME.

Wherein, a release cause value is carried in the UE Context ReleaseRequest message, the release cause is used for indicating the reason forrelease, such as radio connection with US lost, management maintenancecause, user inactivity, or repeated unsuccessful integrity checks withthe UE, etc. When the release cause value is any one of the radioconnection with US lost, the management maintenance cause, or therepeated unsuccessful integrity checks with the UE, etc, an abnormalrelease can be confirmed.

Step 202: after receiving the UE Context Release Request message, theMME determine whether to report according to the release cause value. Ifit is an abnormal release, that is, the release cause value is any oneof the radio connection with UE lost, the management maintenance cause,or the repeated unsuccessful integrity checks with the UE, etc, radiobearer loss information is reported to the gateway while all non-GBRbearers are still preserved.

Step 203: the MME sends a Modify Bearer Request (modify bearer request)message or a Release Access Bearer Request (release access bearerrequest) message to a SGW (servicing gateway), wherein the UE radiobearer loss information is carried in the message.

Wherein, the radio bearer loss information may be a general statement,i.e., without distinguishing particular release causes, or it mayfurther carry a cause value, indicating the particular reason for theradio bearer loss. In this embodiment, the radio bearer loss informationdirects to all non-GBR bearers of the UE, but not one specific non-GBRbearer.

Step 204: after the SGW has received the Modify Bearer Request messageor the Release Access Bearer Request message, and the SGW report the UEradio bearer loss information to a PGW (PDN gateway) through a ModifyBearer Request (modify bearer request) message if UE radio bearer lossinformation is carried in the message is reported.

Thus, the MME completes the reporting of the radio bearer lossinformation, by which the problems of non-GBR bearer interrupting, nomatter whether the service can endure bearer loss on the radio side,which is caused by adopting a bearer release mechanism for non-GBRbearers to notify a gateway after receiving a radio bearer lossinformation by a network-side device MME, and with a deployed PCC,notify the PCRF by the gateway; and of IP address releasing due to therelease of the default bearer and thus the requirement of reattachment,can be solved.

FIG. 3 is a flowchart of a method according to the embodiment, in whicha SGW is responsible for the reporting of radio bearer loss information.The embodiment directs to the EPS (Evolved Packet System) defined by the3GPP standard organization, with eUTRAN as a radio access technique.Referring to FIG. 3, the flow comprises the following steps:

Step 301: if an eNB detects that it is necessary to release a signalingconnection to a UE (User Equipment) and all radio bearers, it sends a S1UE Context Release Request (context release request) message to a MME.

Wherein, a release cause value is carried in the UE Context ReleaseRequest message, to indicate the reason for release, such as the radioconnection with UE lost, the management maintenance cause, userinactivity, and the repeated unsuccessful integrity checks with the UE,etc. When the release cause value is any one of radio connection with UElost, management maintenance cause, or repeated unsuccessful integritychecks with the UE, etc, an abnormal release can be confirmed.

Step 302: the MME sends a Release Access Bearer Request (release accessbearer request) message to a SGW (servicing gateway), wherein a releasecause (cause) value is carried in the message, to request the SGW torelease the connection to the access network device.

Step 303: the SGW receives the Release Access Bearer Request message,and determines whether to report according to the release cause value.If it is an abnormal release, that is, when the release cause value isany one of the radio connection with UE lost, the management maintenancecause, or the repeated unsuccessful integrity checks with the UE, etc, aradio bearer loss information is reported to a PGW while all non-GBRbearers are still preserved.

Step 304: the SGW sends a Modify Bearer Request (modify bearer request)message to a PGW (PDN GW), wherein the UE radio bearer loss informationis carried in the message.

Wherein, the radio bearer loss information may be only a generalstatement, i.e., without distinguishing particular release causes, or itmay further carry a cause value, indicating the particular reason forthe radio bearer loss. In this embodiment, the radio bearer lossinformation directs to all non-GBR bearers of the UE, but not onespecific non-GBR bearer.

Thus, the SGW completes the reporting of the radio bearer lossinformation, by which the problems of non-GBR bearer interrupting, nomatter whether the service can endure bearer loss on the radio side,which is caused by adopting a bearer release mechanism for non-GBRbearers to notify a gateway after receiving a radio bearer lossinformation by a network-side device MME, and with a deployed PCC,notify the PCRF by the gateway; and of IP address releasing due to therelease of the default bearer and thus the requirement of reattachment,can be solved.

FIG. 4 is a flowchart of a method according to the embodiment, in whicha SGSN is responsible for the reporting of radio bearer lossinformation. The embodiment directs to the GPRS (General Packet RadioService) system defined by the 3GPP standard organization, with GERAN(GSM EDGE (Enhanced Data rate for GSM Evolution, enhanced data rate forGSM evolution) Radio Access Network, GSM/EDGE radio accessnetwork)/UTRAN (UMTS Terrestrial Radio Access Network, UMTS terrestrialradio access network)/GSM (Global System for Mobile Communications,global system for mobile communications)) as a radio access technique.Referring to FIG. 4, the flow comprises the following steps:

Step 401: If a RNC detects a RRC (Radio Resource Control, radio resourcecontrol) connection between the RNC and a UE that has been released orneeds to be released, or if the RNC detects that radio resourcesassociated with a UE need to be released, the RNC sends an Iu InterfaceRelease Request (interface release request) message to a SGSN.

Wherein, the Iu interface release request message carries with a releasecause value (cause), such as the radio connection with UE lost, themanagement maintenance cause, user inactivity, and the repeatedunsuccessful integrity checks with the UE, etc. When the release causevalue is any one of the radio connection with UE lost, the managementmaintenance cause, or the repeated unsuccessful integrity checks withthe UE, etc, an abnormal release can be confirmed.

Step 402: the SGSN receives the Iu interface release request message,and determines whether to report according to the release cause value.If it is an abnormal release, that is, when the release cause value isany one of the radio connection with UE lost, the management maintenancecause, or the repeated unsuccessful integrity checks with the UE, etc, aradio bearer loss information is reported to a GGSN while all backgroundclass PDP (Packet Data Protocol, packet data protocol) contexts or allinteractive class PDP contexts or all background class and interactiveclass PDP contexts are still preserved (background class and interactiveclass PDP contexts also are non-GBR bearers).

Step 403: the SGSN sends an update PDP context request (Update PDPContext Request) message to the GGSN, wherein the UE radio bearer lossinformation is carried in the message.

Wherein, the radio bearer loss information may be a general statement,i.e., without distinguishing particular release causes, or it mayfurther carry a cause value, indicating a particular cause of the radiobearer loss. In this embodiment, the radio bearer loss informationdirects to all background class PDP contexts or all interactive classPDP contexts or all background class and interactive class PDP contextsof the UE, but not one specific non-GBR bearer.

According to existing standards, the Update PDP Context Request messagemust specify a PDP context ID, which, in this embodiment, is a primarycontext ID. However, it not intended to demonstrate that radio bearerloss is merely direct to primary on texts.

Thus, the SGSN completes the reporting of the radio bearer lossinformation, by which the problems of non-GBR bearer interrupting, nomatter whether the service can endure radio-side bearer loss, which iscaused by adopting a bearer release mechanism for non-GBR bearers tonotify a gateway after receiving a radio bearer loss information by anetwork-side device SGSN, and with a deployed PCC, notify the PCRF bythe gateway; and of IP address releasing due to the release of thedefault bearer and thus the requirement of reattachment, can be solved.

FIG. 5 is a flowchart of a method of reporting a radio bearer lossinformation provided in an embodiment of this invention, which is alsoapplied on a network-side device MME/SGSN/SGW, in the case that a PDNgateway PGW/GGSN in advance has subscribed a radio bearer lossinformation from the network-side device, the radio bearer lossinformation is reported to the PGW through the MME/SGW. Wherein, contentof this embodiment that is the same as the embodiment shown in FIG. 1will not be described in detail. Referring to FIG. 5, the methodcomprises the following steps:

Step 501: receiving a UE Context Release Request message or ReleaseAccess Bearer Request message or Iu Interface Release Request message,wherein a release cause value is carried in these message.

Wherein, the release cause value is used to indicate a release cause,such as radio connection with UE lost, management maintenance cause,user inactivity, or repeated unsuccessful integrity checks with the UE,etc. When the release cause value is any one of the radio connectionwith UE lost, the management maintenance cause, or the repeatedunsuccessful integrity checks with the UE, etc, an abnormal release canbe confirmed.

Step 502: determining whether a PGW or GGSN has subscribed radio bearerloss information, and if so, proceeds step 503 is performed, otherwisethe process ends. 100661 In this embodiment, it is the MME/SGW thatdetermines whether the PGW has subscribed radio bearer loss information,and it is the SGSN that determine whether the GGSN has subscribed radiobearer loss information.

Wherein, a PCRF may subscribe to radio bearer loss information from thePDN gateway PGW or the GGSN, and the PDN gateway PGW or the GGSNsubscribes to the radio bearer loss information from a network-sidedevice after receiving the subscription from the PCRF.

Wherein, the network-side device in this embodiment may be theMME/SGSN/SGW.

Step 503: determining whether the release cause value indicates anabnormal release, and if so, the step 504 is performed, otherwise theprocess ends.

Step 504: reporting UE radio bearer loss information to a gateway whilepreserving all no-GBR bearers.

Wherein, the gateway may be the PGW or the GGSN. When the method of thisembodiment is applied on the MME, at step 504, a radio bearer lossinformation is reported to the PGW by the MME through the SGW; when themethod of this embodiment is applied on the SGW, at step 504, the radiobearer loss information is reported to the PGW by the SGW; and when themethod of this embodiment is applied on the SGSN, at step 504, the radiobearer loss information is reported to the GGSN by the SGSN.

In this embodiment, there are no limits on the execution sequence ofsteps 502 and 503, for example, the release cause value can bedetermined and then it is determined whether the PGW/GGSN has subscribedthe radio bearer loss information. This embodiment has no limitsthereof.

With the method of reporting a radio bearer loss information provided inthe embodiment of this invention, after a PGW/GGSN has subscribed to theradio bearer loss information, the message is reported to the PGW/GGSN,so that the problems of non-GBR bearer interrupting, no matter whetherthe service can endure radio-side bearer loss, which is caused byadopting a bearer release mechanism for non-GBR bearers to notify thegateway after receiving the radio bearer loss information by thenetwork-side SGSN, and with a deployed PCC, notify the PCRF by thegateway; and of IP address releasing due to the release of the defaultbearer and thus the requirement of reattachment, can be solved.

In order to make the method of the embodiment of FIG. 5 clearer forunderstanding, the method of this embodiment will be described in detailin connection with the flow shown in FIGS. 6 and 7.

FIG. 6 is a flowchart of one embodiment, in which a MME determineswhether to report according to a radio bearer loss information reportrequest from a PGW. This embodiment directs to the EPS (Evolved PacketSystem, evolved packet system) defined by the 3GPP standardorganization, with the eUTRAN as a radio access technique. Referring toFIG. 6, the flow comprises the following steps:

Steps 601-602: a PCRF subscribes to radio bearer loss information from aPGW, wherein the PGW comprises a PCEF (Policy and Charging EnforcementFunction, policy and charging enforcement function). In this embodiment,unless specially stated, the PGW refers to an entity including the PCEF.

Wherein, the LOSS_OF_BEARER information that has been defined can bereused as information value, or new information can be specificallydefined for radio bearer loss. The information may direct to a completeIP-CAN session, or to a specific rule, and this invention does not havelimits thereof.

Step 603: after receiving the Subscribe Radio Bearer Loss Informationrequest of PCRF, the PGW sends an Update Bearer Request (update bearerrequest) message to the SGW, requesting the MME to report theinformation to the PGW after the MME detects radio bearer loss.

Wherein, if the radio bearer loss information subscribed to by the PCRFdirects to the complete IP-CAN session, requesting radio bearer lossfrom the MME involves all non-GBR bearers; if the information subscribedto by the PCRF directs to certain PCC rules, the PGW can still select torequest radio bearer loss for all non-GBR bearers from the MME, or torequest radio bearer loss for specific non-GBR bearers, which are boundto the above PCC rules, from the MME.

For example, the PCRF has subscribed to against PCC rule 1, the PGWfinds that PCC rule 1 is bound to a non-GBR bearer 2, requesting radiobearer loss may merely refer to non-GBR bearer 2.

Steps 604-606: the SGW sends an Update Bearer Request (update Bearerrequest) message to the MME, requiring the MME to report the informationafter detecting radio bearer loss.

Step 607: if an eNB detects that a signaling connection to a UE (UserEquipment) and all radio bearers need to be released, a S1 UE ContextRelease Request message (context release request) is send to the MME.

Wherein, a release cause value is carried in the message to indicate thereason for release, such as radio connection with UE lost, managementmaintenance cause, user inactivity, and repeated unsuccessful integritychecks with the UE, etc. When the release cause value is any one of theradio connection with UE lost, the management maintenance cause, or therepeated unsuccessful integrity checks with the UE, etc, an abnormalrelease can be confirmed.

Step 608: after receiving the UE Context Release Request message, theMME first determines whether the PGW has subscribed to a radio bearerloss information, and then determine whether to report according to therelease cause value; if the PGW requests the MME to report a radiobearer loss information and the release cause value indicates anabnormal release, that is, the release cause value is any one of theradio connection with UE lost, the management maintenance cause, or therepeated unsuccessful integrity checks with the UE, etc, the MME reporta radio bearer loss information to the PGW through the SGW, while allnon-GBR bearers are still preserved.

Step 609: the MME sends a Modify Bearer Request (modify bearer request)message or a Release Access Bearer Request (release access bearerrequest) message to the SGW (servicing gateway), wherein UE radio bearerloss information is carried in the message.

Wherein, the radio bearer loss information may be only a generalstatement, i.e., without distinguishing particular release causes, or itmay further carry a cause value to indicate the particular reason forthe radio bearer loss. In this embodiment, according to the granularityof radio bearer loss requested by the PGW, the radio bearer lossinformation may direct to all non-GBR bearers of the UE, or one specialnon-GBR bearer.

Step 610: after receiving the Modify Bearer Request message or theRelease Access Bearer Request message, if there is a UE radio bearerloss information carried therein, the SGW notifies the UE radio bearerloss information to the PGW (PDN gateway) through a Modify BearerRequest (modify bearer request) message.

Step 611: after receiving the Modify Bearer Request message, the PGWreports the radio bearer loss information to the PCRF through a CCR(Credit Control Request, credit control request) message, and if itdirects to a special PPC rule (rule), the rule affected is reportedthrough a Charging-Rule-Report (charging-rule-report) parameter in theCCR message.

Step 612: after receiving the radio bearer loss information, the PCRFmay notify AF that underlying transport is interrupted; and if someservices cannot be provided due to the radio bearer loss, the PCRF maynotify the PGW to remove PCC rules corresponding to these servicesthrough a CCA (Credit Control Answer) message. Particularly, the PGW isnotified to remove these PCC rules through a Charging-Rule-Remove(charging-rule-remove) parameter in the CCA message.

Step 613: if the PCRF requests to release some PCC rules, according to anew result of bearer binding, the PGW may optionally initiate somebearer operations, such as updating some bearers; and if a non-defaultbearer has its all rules released, a bearer release operation can beinitiated.

Note that although this embodiment has described a PGW subscription to aMME, it is also applicable to a PGW requesting the report of a radiobearer loss information to a SGW (referring to the embodiment shown inFIG. 3), in which case, according to the PGW request, the SGW notifiesthe PGW in an abnormal release of radio bearers. Also, this embodimentis also applicable when a GGSN reports a radio bearer loss informationto a SGSN (referring to the embodiment shown in FIG. 4), wherein theSGSN, according to a request of the GGSN, notifies the GGSN in anabnormal release of radio bearers, which will not be described in detailfor simplicity.

Thus, the MME can determine whether to report according to asubscription request of the PGW (the subscription request can beinitiated from a PCRF).

FIG. 7 is a flowchart of another embodiment, in which a MME determineswhether to report according to a radio bearer loss information reportrequest of a PGW. This embodiment directs to the EPS (Evolved packetSystem) defined by the 3GPP standard organization, with the eUTRAN as aradio access technique. Different to the flow shown in FIG. 6, insteadof the GTP (GPRS Tunneling Protocol, GPRS tunneling protocol), the PMIP(Proxy Mobile IP, proxy mobile IP) protocol is adopted between the SGWand the PGW. In such a case, the PGW is unable to request the MME toreport radio bearer loss through the PMIP protocol or execute bearerbinding, and these functions are realized by the SGW including a BBERF(Bearing Binding and Event Report Function, bearing binding and eventreport function). Referring to FIG. 7 the flow comprises the followingsteps:

Steps 701-702: a PCRF subscribes to radio bearer loss information fromthe SGW. In this embodiment, unless specially stated, the SGW refers toan entity including the BBERF.

Wherein, the LOSS OF BEARER information that has been defined can bereused for information value, or new information can be definedspecifically for radio bearer loss. The information may direct to acomplete IP-CAN session, or a specific rule, and this invention does nothave limits thereof.

Steps 703-704: after receiving the Subscribe Radio Bearer LossInformation request, the SGW sends an Update Bearer Request (updatebearer request) message to the MME, requesting the MME to report theinformation to the PCEF after detecting the loss of radio bearers.

Wherein, if the radio bearer loss information subscribed to by the PCRFdirects to the complete session, requesting a radio bearer lossinformation from the MME involves all non-GBR bearers. If the radiobearer loss information subscribed to by the PCRF directs to some QoSrules, the SGW can still select to request radio bearer loss for allnon-GBR bearers from the MME, or to request radio bearer loss for aspecific non-GBR bearers, which are bound to the above QoS rules, fromthe MME.

Step 705: if an eNB detects that a signaling connection to a UE (userequipment) and all radio bearers need to be released, a S1 UE ContextRelease Request (context release request) message is send to the MME.

Wherein, a release cause value carried in the information is used forindicating the reason for release, such as radio connection with UElost, management maintenance cause, user inactivity, and repeatedunsuccessful integrity checks with the UE, etc. When the release causevalue is any one of the radio connection with UE lost, the managementmaintenance cause, or the repeated unsuccessful integrity checks withthe UE, etc, an abnormal release can be confirmed.

Step 706: after receiving the UE Context Release Request message, theMME first determines whether the PGW has subscribed to radio bearer lossinformation, and then determines whether to report according to therelease cause value. If the SGW requests the MME to report a radiobearer loss information and the release cause value indicates anabnormal release, that is, a release cause value other than userinactivity (user inactivity), the MME reports a radio bearer lossinformation to a gateway, while all non-GBR bearers are still preserved.

Step 707: the MME sends a Modify Bearer Request (modify Bearer request)message or a Release Access Bearer Request (Release Access BearersRequest) message to the SGW.

Wherein, the UE radio bearer loss information is carried in theinformation. The radio bearer loss information may be a generalstatement, i.e., without distinguishing particular release causes, or itmay further carry a cause value to indicate a particular cause of theloss of radio bearers. In this embodiment, according to the granularityof radio bearer loss requested by the PGW, the radio bearer lossinformation may direct to all non-GBR bearers of the UE, or one specificnon-GBR bearer.

Step 708: after receiving the Modify Bearer Request message, the SGWreports the radio bearer loss information to the PCRF through a CCR(Credit Control Request, credit control request) message; and if itdirects to a specific QoS rule, the rule affected is reported through aCharging-Rule-Report parameter in the CCR message.

Step 709: after receiving the radio bearer loss information, the PCRFmay notify AF that underlying transport is interrupted, and if someservices cannot be resumed due to the radio bearer loss, the PCRF maynotify the SGW to remove PCC rules and Qos rules corresponding to theseservices through a CCA (Credit Control Answer) message. Particularly,the SGW is notified to remove these PCC rules and QoS rules through aCharging-Rule-Remove (charging-rule-remove) parameter in the CCAmessage.

Step 710: if the PCRF requests to release (i.e., to remove) some QoSrules, the SGW may optionally initiate some bearer operations accordingto a new result of bearer binding, such as updating some bearers; and ifa non-default bearer has its all rules released, a bearer releaseoperation can be initiated (for a default bearer, it cannot bereleased).

Steps 711-712: the PCRF requests the PGW (including a PCEF) to removethe PCC rules.

Thus, the MME can determine whether to report according to asubscription request of the SGW (the subscription request can beinitiated from the PCRF).

In the embodiments shown in FIGS. 6 and 7, if there is no a PCCdeployed, the dashed-line steps are not present.

With the method of reporting a radio bearer loss information provided inthe embodiment of this invention, the problems of non-GBR bearerinterrupting, no matter whether the service can endure radio-side bearerloss, which is caused by adopting a bearer release mechanism for non-GBRbearers to notify a gateway after receiving a radio bearer lossinformation by a MME, and with a deployed PCC, notify the PCRF by thegateway; and of IP address releasing due to the release of a defaultbearer and thus the requirement of reattachment, can be solved.

FIG. 8 is a component block diagram of a Moving Management Entity MMEprovided in an embodiment of this invention. Referring to FIG. 8, theMME comprises:

a receiving unit 81, configured to receive a UE Context Release Requestmessage carrying a release cause value sent by an Evolved Node B eNB.

Wherein, the release cause value is used to indicate a release cause,such as radio connection with UE lost, management maintenance cause,user inactivity, or repeated unsuccessful integrity checks with the UE,etc. When the release cause value is any one of the radio connectionwith UE lost, the management maintenance cause, or the repeatedunsuccessful integrity checks with the UE, etc, an abnormal release canbe confirmed.

a reporting unit 82, configured to report radio bearer loss informationto a PGW through a SGW when the release cause value indicates anabnormal release;

a processing unit 83, configured to preserve non-GBR bearers when therelease cause value indicates an abnormal release.

Wherein, when a device on the radio access network side (such as eNB)detects that it is necessary to release a radio signaling connection toa UE and all radio bearers, it sends a UE Context Release Requestmessage carrying a release cause value to a network-side device (such asa MME) to notify the MME of the interruption of the connection to thatUE. At that point, after receiving the corresponding UE Context Releasemessage carrying the release cause value, the MME determines whether toreport a radio bearer loss information according to the release causevalue, Wherein, if the release cause value is any one of the radioconnection with UE lost, the management maintenance cause, or therepeated unsuccessful integrity checks with the UE, etc, a radio bearerloss information for the UE is reported to a PGW through a SGW, whileall non-GBR bearers are still preserved on the MME.

In one embodiment, the report unit 82 is particularly used to send aModify Bearer Request message or a Release Access Bearer Request messageboth carrying radio bearer loss information to a SGW, so as to send theModify Bearer Request message carrying radio bearer loss information toa PGW through the SGW.

In one embodiment, the MME may further comprise:

a determining unit 84, configured to determine whether a radio bearerloss information is subscribed to by the PGW after receiving the UEContext Release message carrying a release cause sent by the EvolvedNode B eNB; if the radio bearer loss information is subscribed to by thePGW, determining whether the release cause value is an abnormal release,and reporting the result of the determination to the reporting unit 82and the processing unit 83.

Various components of the MME of this embodiment are used to implementsteps of the method in the embodiment shown in FIG. 2 respectively.Because each of those steps has been described in detail in theembodiment shown in FIG. 2, they will not be repeated herein.

With the MME provided in this embodiment, the problems of non-GBR bearerinterrupting, no matter whether the service can endure bearer loss onthe radio side, which is caused by adopting a bearer release mechanismfor non-GBR bearers to notify a gateway after receiving a radio bearerloss information by a MME, and with a deployed PCC, notify a PCRF by thegateway; and of IP address releasing due to the release of the defaultbearer and thus the requirement of reattachment, can be solved.

FIG. 9 is a component block diagram of a Servicing gateway SGW providedin an embodiment of this invention. Referring to FIG. 9, the SGWcomprises:

a receiving unit 91, configured to receive a Release Access BearerRequest message carrying a release cause value sent by a MME.

Wherein, the release cause value is used to indicate a release cause,such as radio connection with UE lost, management maintenance cause,user inactivity, or repeated unsuccessful integrity checks with the UE,etc. When the release cause value is any one of the radio connectionwith UE lost, the management maintenance cause, or the repeatedunsuccessful integrity checks with the UE, etc, an abnormal release canbe confirmed.

a reporting unit 92, configured to report radio bearer loss informationto a PGW when the release cause value indicates an abnormal release;

a processing unit 93, configured to preserve all non-GBR bearers whenthe release cause value indicates an abnormal release.

Wherein, after receiving a corresponding UE Context Release Messagecarrying a release cause value, instead of reporting radio bearer lossinformation, the MME forwards the release cause value to the SGW througha Release Access Bearer Request message, and it is the SGW which thenperforms the reporting of the radio bearer loss information.

Wherein, after receiving the Release Access Bearer Request messagecarrying a release cause value, the SGW determines whether to reportradio bearer loss information according to the release cause value.Wherein for an abnormal release, that is, if the release cause value isany one of the radio connection with UE lost, the management maintenancecause, or the repeated unsuccessful integrity checks with the UE, etc, aradio bearer loss information for the UE is reported to a PGW, while allnon-GBR bearers are still preserved on the SGW.

In one embodiment, the reporting unit 92 is particularly used to send aModify Bearer Request message carrying radio bearer loss information toa PGW.

In one embodiment, the SGW may further comprise:

a determining unit 94, configured to determine whether a radio bearerloss information is subscribed to by the PGW after receiving the ReleaseAccess Bearer Request message carrying a release cause value sent by theMME; if the radio bearer loss information is subscribed to by the PGW,determining whether the release cause value is an abnormal release; andreporting the result of the determination to the reporting unit 92 andthe processing unit 93.

Various components of the SGW of this embodiment are used to implementsteps of the method in the embodiment shown in FIG. 3 respectively.Because each of those steps has been described in detail in theembodiment shown in FIG. 3, they will not be repeated herein.

With the SGW provided in this embodiment, the problems of non-GBR bearerinterrupting, no matter whether the service can endure bearer loss onthe radio side, which is caused by adopting a bearer release mechanismfor non-GBR bearers to notify a gateway after receiving a radio bearerloss information by a MME, and with a deployed PCC, notify a PCRF by thegateway; and of IP address releasing due to the release of the defaultbearer and thus the requirement of reattachment, can be solved.

FIG. 10 is a component block diagram of a Serving GPRS support Node SGSNprovided in an embodiment of this invention. Referring to FIG. 10, theSGSN comprises:

a receiving unit 1001, configured to receive a Iu Interface ReleaseRequest message carrying a release cause value sent by a RNC.

Wherein, the release cause value is used to indicate the reason forrelease, such as radio connection with UE lost, management maintenancecause, user inactivity, or repeated unsuccessful integrity checks withthe UE, etc. When the release cause value is any one of the radioconnection with UE lost, the management maintenance cause, or therepeated unsuccessful integrity checks with the UE, etc, an abnormalrelease can be confirmed.

a reporting unit 1002, configured to report radio bearer lossinformation to a gateway when the release cause value indicates anabnormal release;

a processing unit 1003, configured to preserve all non-GBR bearers whenthe release cause value indicates an abnormal release.

In this embodiment, when a device on the radio access network side (suchas RNC) detects that it is necessary to release a radio signalingconnection to a UE and all radio bearers, it sends a Iu InterfaceRelease Request message carrying a release cause value to thenetwork-side device (such as SGSN) to notify the SGSN that a radioconnection to the UE has been interrupted. At that point, afterreceiving the Iu Interface Release Request message, the SGSN performsthe reporting of radio bearer loss information.

Wherein, after receiving the Iu Interface Release Request messagecarrying a release cause value, the SGSN determines whether to reportradio bearer loss information according to the release cause value.Wherein for an abnormal release, that is, if the release cause value isany one of the radio connection with UE lost, the management maintenancecause, or the repeated unsuccessful integrity checks with the UE, etc,radio bearer loss information for the UE is reported to a GGSN, whileall non-GBR bearers are still preserved on the SGSN.

In one embodiment, the report unit 1002 is particularly used to send anUpdate PDP Context Request message carrying radio bearer lossinformation to the Gateway GPRS support Node GGSN.

In one embodiment, the SGSN may further comprise:

a determining unit 1004, configured to determine whether a radio bearerloss information is subscribed to by the GGSN after the receiving unit1001 has received the Iu Interface Release Request message carrying arelease cause value sent by the Radio Network Controller RNC; if theradio bearer loss information is subscribed to by the GGSN, determiningwhether the release cause value is an abnormal release, and reportingthe result of the determination to the reporting unit 1002 and theprocessing unit 1003.

Various components of the SGSN of this embodiment are used to implementsteps of the method in the embodiment shown in FIG. 4 respectively.Because each of those steps has been described in detail in theembodiment shown in FIG. 4, they will not be repeated herein.

With the SGSN provided in this embodiment, the problems of non-GBRbearer interrupting, no matter whether the service can endure bearerloss on the radio side, which is caused by adopting a bearer releasemechanism for non-GBR bearers to notify a gateway after receiving aradio bearer loss information by a GGSN, and with a deployed PCC, notifya PCRF by the gateway; and of IP address releasing due to the release ofthe default bearer and thus the requirement of reattachment, can besolved.

Steps of methods or algorithms described with reference to embodimentsdisclosed herein can be implemented in hardware directly, softwaremodules executed on a processor, or a combination thereof. Softwaremodules can be placed in Random Access Memory (RAM), Read Only Memory(ROM), electrically programmable ROM, electrically erasable andprogrammable ROM, registers, hard disks, removable magnetic disks,CD-ROMs, or any other storage mediums well known by those skilled in theart.

The objects, technical solutions and beneficial effects of presentinvention have been described in further detail with the aboveparticular embodiments. It should be understood that the above aremerely specific embodiments of the present invention, but is notintended to limit the scope of this invention. Any modifications,equivalent alternatives, or improvements are also covered in the scopeof embodiments of this invention as falling within the spirit andprinciple of embodiments of this invention.

1. A radio bearer loss information reporting method, comprising:receiving one of the group consisting of a user equipment (UE) contextrelease request message, a release access bearer request message, and anIu interface release request message, wherein each of the user equipment(UE) context release request message the release access bearer requestmessage and the Iu interface release request message carries a releasecause value; if the release cause value indicates an abnormal release,reporting the radio bearer loss information to a gateway whilepreserving non-guaranteed bandwidth (non-GBR) bearers.
 2. The methodaccording to claim 1, wherein when the method is applied on a mobilitymanagement entity (MME), the receiving one of the group consisting ofthe user equipment (UE) context release request message the releaseaccess bearer request message, and the Iu interface release requestmessage, comprises receiving the user equipment (UE) context releaserequest message carrying the release cause value sent by an evolved NodeB (eNB).
 3. The method according to claim 2, wherein the reporting radiobearer loss information to the gateway comprises: sending one of thegroup consisting of a modify bearer request message and a release accessbearer request message to a servicing gateway (SGW), wherein each of themodify bearer request message and the release access bearer requestmessage carries the radio bearer loss information, and the modify bearerrequest message carrying the radio bearer loss information is sent to apacket data network (PDN) gateway (PGW) through the SGW.
 4. The methodaccording to claim 1, wherein when the method is applied on a servinggateway (SGW), the receiving one of the group consisting of the userequipment (UE) context release request message the release access bearerrequest message and the Iu interface release request message comprises:receiving the release access bearer request message carrying the releasecause value sent by the MME.
 5. The method according to claim 4, whereinthe reporting radio bearer loss information to the gateway comprises:sending a modify bearer request message carrying the radio bearer lossinformation to a packet data network (PDN) gateway (PGW).
 6. The methodaccording to claim 1, wherein when the method is applied on a servingGPRS support Node (SGSN), the receiving one of the group consisting ofthe user equipment (UE) context release request message the releaseaccess bearer request message, and the Iu interface release requestmessage, comprises: receiving the Iu interface Release Request messagecarrying the release cause value sent by a radio network controller(RNC).
 7. The method according to claim 6, wherein the reporting theradio bearer loss information to the gateway comprises: sending anupdate Packet Data Protocol (PDP) context request message carrying theradio bearer loss information to a gateway GPRS support Node (GGSN). 8.A mobility management entity (MME), comprising: a receiving unit,configured to receive a UE context release request message carrying arelease cause value sent by an evolved Node B (eNB); a reporting unit,configured to report radio bearer loss information to a gateway when therelease cause value indicates an abnormal release ; a processing unit,configured to preserve non-GBR bearers when the release cause valueindicates the abnormal release.
 9. The MME according to claim 8, whereinthe release cause value includes: one of the group consisting of radioconnection with UE lost, management maintenance cause, user inactivity,and repeated unsuccessful integrity checks with the UE; when the releasecause value is one of the group consisting of the radio connection withUE lost, the management maintenance cause, and the repeated unsuccessfulintegrity checks with the UE, the abnormal release occurs.
 10. The MMEaccording to claim 8, wherein the reporting unit is configured to sendone of the group consisting of a modify bearer request message and arelease access bearer request message wherein each of the modify bearerrequest message and the release access bearer request message carriesthe radio bearer loss information to a serving gateway (SGW), so thatthe modify bearer request message carrying the radio bearer lossinformation is sent to a packet data network (PDN) gateway (PGW) by theSGW.
 11. A serving gateway (SGW), comprising: a receiving unit,configured to receive a release access bearer request message carrying arelease cause value sent by a mobility management entity (MME); areporting unit, configured to report radio bearer loss information to apacket data network (PDN) gateway (PGW) when the release cause valueindicates an abnormal release; a processing unit, configured to preservenon-GBR bearers when the release cause value indicates the abnormalrelease.
 12. The SGW according to claim 11, wherein the release causevalue includes: one of the group consisting of radio connection with UElost, management maintenance cause, user inactivity, and repeatedunsuccessful integrity checks with the UE; when the release cause valueis one of the group consisting of the radio connection with the UE lost,the management maintenance cause, and the repeated unsuccessfulintegrity checks with the UE, the abnormal release occurs.
 13. A servingGPRS support Node (SGSN), comprising: a receiving unit, configured toreceive an Iu interface release request message carrying a release causevalue sent by a radio network controller (RNC); a reporting unit,configured to report radio bearer loss information to a gateway when therelease cause value indicates the abnormal release; a processing unit,configured to preserve non-GBR bearers when the release cause valueindicates an abnormal release.
 14. The SGSN according to claim 13,wherein the release cause value includes: one of the group consisting ofradio connection with UE lost, management maintenance cause, userinactivity, and repeated unsuccessful integrity checks with the UE; whenthe release cause value is one of the group consisting of the radioconnection with the UE lost, the management maintenance cause, and therepeated unsuccessful integrity checks with the UE, the abnormal releaseoccurs.
 15. The SGSN according to claim 13, wherein the reporting unitis configured to send an update Packet Data Protocol (PDP) contextrequest message carrying the radio bearer loss information to a gatewayGPRS support Node (GGSN).